The subject matter disclosed herein relates to the art of turbomachines and, more particularly, to a measurement fixture for a turbomachine bucket tip shroud.
Turbomachines include a compressor portion linked to a turbine portion through a common compressor/turbine shaft and a combustor assembly. An inlet airflow is passed through an air intake toward the compressor portion. In the compressor portion, the inlet airflow is compressed through a number of sequential stages toward the combustor assembly. In the combustor assembly, the compressed airflow mixes with a fuel to form a combustible mixture. The combustible mixture is combusted in the combustor assembly to form hot gases. The hot gases are guided along a hot gas path of the turbine portion through a transition piece. The hot gases expand along a hot gas path through a number of turbine stages acting upon turbine bucket airfoils mounted on wheels to create work that is output, for example, to power a generator.
Bucket airfoils may include a tip shroud having a Z-shaped geometry. The Z-shaped geometry establishes a sealing ring having small gaps between adjacent bucket airfoil tip shrouds. During operation, bucket airfoils may twist. A twist in one or more bucket airfoils may enlarge the gaps allowing hot gases to exit prematurely from the hot gas path. Changes in the gaps may also cause bucket airfoils to interact with one another in a manner that could result in damage. Bucket airfoils are periodically removed and measured to determine if, and how much, twisting may have occurred.